Arrayed on the Ladies' Day banquet table were yellow-green avocado pear halves stuffed with crabmeat and mayonnaise, and platters of rare roast beef and cold chicken, and every so often a cut-glass bowl heaped with black caviar. I hadn't had time to eat any breakfast at the hotel cafeteria that morning, except for a cup of overstewed coffee so bitter it made my nose curl, and I was starving.

...

I had a vision of the celestially white kitchens of Ladies' Day stretching into infinity. I saw avocado pear after avocado pear being stuffed with crabmeat and mayonnaise under brilliant lights. I saw the delicate, pink-mottled claw meat poking seductively through its blanket of mayonnaise and the bland yellow pear cup with its rim of alligator-green cradling the whole mess.Poison.

Last Sunday, the summer solstice, was a day I wanted (inexplicably) to spend with some seafood. I can't explain it, except to say that the idea of waking early, leaving home at sunrise to visit a fish market, and then turning my wares into something delicious, sounded like the right way to use those few extra precious minutes of sunlight. However, Billingsgate Market isn't open on a Sunday. So Saturday - almost the longest day of the year - it had to be.

I set my alarm for 3.45am, but ended up waking up at least every hour in the lead up to that time. I was convinced I'd sleep through my alarm and miss the market altogether, as my friend Anna did - I had a text from her at 10.15am apologising profusely for having just woken up. Once out of bed, I walked through the park as the sun was coming up, jumped on a night bus and headed to the East London Docklands.

Billingsgate Market has been located in the Isle of Dogs since 1982. Before its move, it had been a fixture in the City of London since the 16th Century. Though it is predominantly a wholesale market, opening at 4am to sell to restaurants and caterers, members of the public are very much welcome, and much of what is on offer can be purchased in reasonable sized quantities for the home cook. The stall holders are also generous with their help and advice - though everything does move at a speedy pace! I walked away with two Dover Sole (£2), a kilogram of prawns (£7), about 20 whole squid (£9), a few oysters (60p each) and a 60cm long side of salmon (£12). There will be more on these in upcoming posts.

I also got my hands on a couple of live brown crabs. The woman I was standing next to, who fearlessly thrust her hands into the buckets of huge crabs and dropped ten into a huge bag within a minute, helped me choose a couple of good ones. Her tip is to go for crabs that feel heavy for their size - which makes absolute sense, given that you're interested in the meat inside the shell. She handed me a couple so I could judge them, and we chose two weighty ones. Getting them home on the bus was an interesting adventure, as was being creeped out by continually mistaking the sound of the crabs shuffling around in my kitchen for an intruder.

If you don't fancy killing crabs yourself for this recipe, then do buy white crab meat, or cooked whole crabs instead. In the interest of full disclosure, I struggled with it lots more than I anticipated - practically and, because I was worried I wasn't doing it right, ethically. As such, the recipe below starts from an assumption that you have a cooked crab available. If you want to start from live crabs, I found these instructions really useful. Importantly, ignore every film you've ever seen and do make sure the crab is dead before you drop it in a pot of boiling water - it's better for the crab, and better for you (taste-wise).

So, to the dish itself. I've written previously about my love for The Bell Jar and, although it's not the nicest foodie moment (the food poisoning isn't something to aim for), crab meat always makes me think of the scene above. The wonderfully retro mayonnaise salad, inside half a pale green avocado, is just perfect for a Ladies Luncheon. For Esther Greenwood, still new to New York, the meal described would have been an exciting spread; she goes on to note that, before New York, she'd never eaten out at a proper restaurant. It's a shame, then, that the meal ends on such an awful note. A valid life lesson learnt though: keep your crab in the fridge.

EquipmentCollection of tools for taking apart a crab - including a hammer and a skewer Mixing bowlWhiskKnife and chopping board

1. Place your crab upside down on the table in front of you. To get at the white meat, twist the legs and claws off the body. Work with them one by one. Crack their shells with the hammer, and pull the meat out, then set it aside. The claws have a significant amount of meat in them, so make sure you crack each part, and use a skewer to get into the crevices.

2. You don't need the brown meat for this recipe but, to access it, keep the crab facing belly-up. Place your thumbs under the base of the centre piece of the shell and push up. The body will come out. Discard the white gills and scoop out the brown meat.

3. To make the mayonnaise, whisk the egg yolk until thick and creamy. Whisk in the lemon juice and mustard, along with a pinch of salt and pepper. Very slowly add the oil to the yolk, whisking continuously. Keep your eye on the oil, rather than the mayonnaise, and don't let it pour out too quickly. You just want a couple of drops every few seconds. Once the mayonnaise has started to thicken, you can pour a little faster. Continue whisking until you have used most of the oil and the mayonnaise is very thick.

4. Finely chop the spring onion, parsley and dill. Combine the crab meat, two or three tablespoons of the mayonnaise and the herbs and spring onion in a bowl. Taste for seasoning.

5. Cut the avocado in half, remove the stone and peel off the skin. Take a small slice off the base of the avocado, so it will sit on the serving plate with a bit of stability. Spoon a generous amount of the crab mix into the hole left by the shell. Squeeze some lemon over the top and serve. With a martini, of course.